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platform/x86: move rfkill for Dell Mini 1012 to compal-laptop
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / fs / proc / base.c
blob8418fcc0a6abd1efb58c0c66efdb1fef411d81d8
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/rcupdate.h>
67 #include <linux/kallsyms.h>
68 #include <linux/stacktrace.h>
69 #include <linux/resource.h>
70 #include <linux/module.h>
71 #include <linux/mount.h>
72 #include <linux/security.h>
73 #include <linux/ptrace.h>
74 #include <linux/tracehook.h>
75 #include <linux/cgroup.h>
76 #include <linux/cpuset.h>
77 #include <linux/audit.h>
78 #include <linux/poll.h>
79 #include <linux/nsproxy.h>
80 #include <linux/oom.h>
81 #include <linux/elf.h>
82 #include <linux/pid_namespace.h>
83 #include <linux/fs_struct.h>
84 #include <linux/slab.h>
85 #include "internal.h"
86
87 /* NOTE:
88 * Implementing inode permission operations in /proc is almost
89 * certainly an error. Permission checks need to happen during
90 * each system call not at open time. The reason is that most of
91 * what we wish to check for permissions in /proc varies at runtime.
92 *
93 * The classic example of a problem is opening file descriptors
94 * in /proc for a task before it execs a suid executable.
95 */
96
97 struct pid_entry {
98 char *name;
99 int len;
100 mode_t mode;
101 const struct inode_operations *iop;
102 const struct file_operations *fop;
103 union proc_op op;
104 };
105
106 #define NOD(NAME, MODE, IOP, FOP, OP) { \
107 .name = (NAME), \
108 .len = sizeof(NAME) - 1, \
109 .mode = MODE, \
110 .iop = IOP, \
111 .fop = FOP, \
112 .op = OP, \
113 }
114
115 #define DIR(NAME, MODE, iops, fops) \
116 NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} )
117 #define LNK(NAME, get_link) \
118 NOD(NAME, (S_IFLNK|S_IRWXUGO), \
119 &proc_pid_link_inode_operations, NULL, \
120 { .proc_get_link = get_link } )
121 #define REG(NAME, MODE, fops) \
122 NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {})
123 #define INF(NAME, MODE, read) \
124 NOD(NAME, (S_IFREG|(MODE)), \
125 NULL, &proc_info_file_operations, \
126 { .proc_read = read } )
127 #define ONE(NAME, MODE, show) \
128 NOD(NAME, (S_IFREG|(MODE)), \
129 NULL, &proc_single_file_operations, \
130 { .proc_show = show } )
131
132 /*
133 * Count the number of hardlinks for the pid_entry table, excluding the .
134 * and .. links.
135 */
136 static unsigned int pid_entry_count_dirs(const struct pid_entry *entries,
137 unsigned int n)
138 {
139 unsigned int i;
140 unsigned int count;
141
142 count = 0;
143 for (i = 0; i < n; ++i) {
144 if (S_ISDIR(entries[i].mode))
145 ++count;
146 }
147
148 return count;
149 }
150
151 static int get_fs_path(struct task_struct *task, struct path *path, bool root)
152 {
153 struct fs_struct *fs;
154 int result = -ENOENT;
155
156 task_lock(task);
157 fs = task->fs;
158 if (fs) {
159 read_lock(&fs->lock);
160 *path = root ? fs->root : fs->pwd;
161 path_get(path);
162 read_unlock(&fs->lock);
163 result = 0;
164 }
165 task_unlock(task);
166 return result;
167 }
168
169 static int get_nr_threads(struct task_struct *tsk)
170 {
171 unsigned long flags;
172 int count = 0;
173
174 if (lock_task_sighand(tsk, &flags)) {
175 count = atomic_read(&tsk->signal->count);
176 unlock_task_sighand(tsk, &flags);
177 }
178 return count;
179 }
180
181 static int proc_cwd_link(struct inode *inode, struct path *path)
182 {
183 struct task_struct *task = get_proc_task(inode);
184 int result = -ENOENT;
185
186 if (task) {
187 result = get_fs_path(task, path, 0);
188 put_task_struct(task);
189 }
190 return result;
191 }
192
193 static int proc_root_link(struct inode *inode, struct path *path)
194 {
195 struct task_struct *task = get_proc_task(inode);
196 int result = -ENOENT;
197
198 if (task) {
199 result = get_fs_path(task, path, 1);
200 put_task_struct(task);
201 }
202 return result;
203 }
204
205 /*
206 * Return zero if current may access user memory in @task, -error if not.
207 */
208 static int check_mem_permission(struct task_struct *task)
209 {
210 /*
211 * A task can always look at itself, in case it chooses
212 * to use system calls instead of load instructions.
213 */
214 if (task == current)
215 return 0;
216
217 /*
218 * If current is actively ptrace'ing, and would also be
219 * permitted to freshly attach with ptrace now, permit it.
220 */
221 if (task_is_stopped_or_traced(task)) {
222 int match;
223 rcu_read_lock();
224 match = (tracehook_tracer_task(task) == current);
225 rcu_read_unlock();
226 if (match && ptrace_may_access(task, PTRACE_MODE_ATTACH))
227 return 0;
228 }
229
230 /*
231 * Noone else is allowed.
232 */
233 return -EPERM;
234 }
235
236 struct mm_struct *mm_for_maps(struct task_struct *task)
237 {
238 struct mm_struct *mm;
239
240 if (mutex_lock_killable(&task->cred_guard_mutex))
241 return NULL;
242
243 mm = get_task_mm(task);
244 if (mm && mm != current->mm &&
245 !ptrace_may_access(task, PTRACE_MODE_READ)) {
246 mmput(mm);
247 mm = NULL;
248 }
249 mutex_unlock(&task->cred_guard_mutex);
250
251 return mm;
252 }
253
254 static int proc_pid_cmdline(struct task_struct *task, char * buffer)
255 {
256 int res = 0;
257 unsigned int len;
258 struct mm_struct *mm = get_task_mm(task);
259 if (!mm)
260 goto out;
261 if (!mm->arg_end)
262 goto out_mm; /* Shh! No looking before we're done */
263
264 len = mm->arg_end - mm->arg_start;
265
266 if (len > PAGE_SIZE)
267 len = PAGE_SIZE;
268
269 res = access_process_vm(task, mm->arg_start, buffer, len, 0);
270
271 // If the nul at the end of args has been overwritten, then
272 // assume application is using setproctitle(3).
273 if (res > 0 && buffer[res-1] != '\0' && len < PAGE_SIZE) {
274 len = strnlen(buffer, res);
275 if (len < res) {
276 res = len;
277 } else {
278 len = mm->env_end - mm->env_start;
279 if (len > PAGE_SIZE - res)
280 len = PAGE_SIZE - res;
281 res += access_process_vm(task, mm->env_start, buffer+res, len, 0);
282 res = strnlen(buffer, res);
283 }
284 }
285 out_mm:
286 mmput(mm);
287 out:
288 return res;
289 }
290
291 static int proc_pid_auxv(struct task_struct *task, char *buffer)
292 {
293 int res = 0;
294 struct mm_struct *mm = get_task_mm(task);
295 if (mm) {
296 unsigned int nwords = 0;
297 do {
298 nwords += 2;
299 } while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */
300 res = nwords * sizeof(mm->saved_auxv[0]);
301 if (res > PAGE_SIZE)
302 res = PAGE_SIZE;
303 memcpy(buffer, mm->saved_auxv, res);
304 mmput(mm);
305 }
306 return res;
307 }
308
309
310 #ifdef CONFIG_KALLSYMS
311 /*
312 * Provides a wchan file via kallsyms in a proper one-value-per-file format.
313 * Returns the resolved symbol. If that fails, simply return the address.
314 */
315 static int proc_pid_wchan(struct task_struct *task, char *buffer)
316 {
317 unsigned long wchan;
318 char symname[KSYM_NAME_LEN];
319
320 wchan = get_wchan(task);
321
322 if (lookup_symbol_name(wchan, symname) < 0)
323 if (!ptrace_may_access(task, PTRACE_MODE_READ))
324 return 0;
325 else
326 return sprintf(buffer, "%lu", wchan);
327 else
328 return sprintf(buffer, "%s", symname);
329 }
330 #endif /* CONFIG_KALLSYMS */
331
332 #ifdef CONFIG_STACKTRACE
333
334 #define MAX_STACK_TRACE_DEPTH 64
335
336 static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns,
337 struct pid *pid, struct task_struct *task)
338 {
339 struct stack_trace trace;
340 unsigned long *entries;
341 int i;
342
343 entries = kmalloc(MAX_STACK_TRACE_DEPTH * sizeof(*entries), GFP_KERNEL);
344 if (!entries)
345 return -ENOMEM;
346
347 trace.nr_entries = 0;
348 trace.max_entries = MAX_STACK_TRACE_DEPTH;
349 trace.entries = entries;
350 trace.skip = 0;
351 save_stack_trace_tsk(task, &trace);
352
353 for (i = 0; i < trace.nr_entries; i++) {
354 seq_printf(m, "[<%p>] %pS\n",
355 (void *)entries[i], (void *)entries[i]);
356 }
357 kfree(entries);
358
359 return 0;
360 }
361 #endif
362
363 #ifdef CONFIG_SCHEDSTATS
364 /*
365 * Provides /proc/PID/schedstat
366 */
367 static int proc_pid_schedstat(struct task_struct *task, char *buffer)
368 {
369 return sprintf(buffer, "%llu %llu %lu\n",
370 (unsigned long long)task->se.sum_exec_runtime,
371 (unsigned long long)task->sched_info.run_delay,
372 task->sched_info.pcount);
373 }
374 #endif
375
376 #ifdef CONFIG_LATENCYTOP
377 static int lstats_show_proc(struct seq_file *m, void *v)
378 {
379 int i;
380 struct inode *inode = m->private;
381 struct task_struct *task = get_proc_task(inode);
382
383 if (!task)
384 return -ESRCH;
385 seq_puts(m, "Latency Top version : v0.1\n");
386 for (i = 0; i < 32; i++) {
387 if (task->latency_record[i].backtrace[0]) {
388 int q;
389 seq_printf(m, "%i %li %li ",
390 task->latency_record[i].count,
391 task->latency_record[i].time,
392 task->latency_record[i].max);
393 for (q = 0; q < LT_BACKTRACEDEPTH; q++) {
394 char sym[KSYM_SYMBOL_LEN];
395 char *c;
396 if (!task->latency_record[i].backtrace[q])
397 break;
398 if (task->latency_record[i].backtrace[q] == ULONG_MAX)
399 break;
400 sprint_symbol(sym, task->latency_record[i].backtrace[q]);
401 c = strchr(sym, '+');
402 if (c)
403 *c = 0;
404 seq_printf(m, "%s ", sym);
405 }
406 seq_printf(m, "\n");
407 }
408
409 }
410 put_task_struct(task);
411 return 0;
412 }
413
414 static int lstats_open(struct inode *inode, struct file *file)
415 {
416 return single_open(file, lstats_show_proc, inode);
417 }
418
419 static ssize_t lstats_write(struct file *file, const char __user *buf,
420 size_t count, loff_t *offs)
421 {
422 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
423
424 if (!task)
425 return -ESRCH;
426 clear_all_latency_tracing(task);
427 put_task_struct(task);
428
429 return count;
430 }
431
432 static const struct file_operations proc_lstats_operations = {
433 .open = lstats_open,
434 .read = seq_read,
435 .write = lstats_write,
436 .llseek = seq_lseek,
437 .release = single_release,
438 };
439
440 #endif
441
442 /* The badness from the OOM killer */
443 unsigned long badness(struct task_struct *p, unsigned long uptime);
444 static int proc_oom_score(struct task_struct *task, char *buffer)
445 {
446 unsigned long points = 0;
447 struct timespec uptime;
448
449 do_posix_clock_monotonic_gettime(&uptime);
450 read_lock(&tasklist_lock);
451 if (pid_alive(task))
452 points = badness(task, uptime.tv_sec);
453 read_unlock(&tasklist_lock);
454 return sprintf(buffer, "%lu\n", points);
455 }
456
457 struct limit_names {
458 char *name;
459 char *unit;
460 };
461
462 static const struct limit_names lnames[RLIM_NLIMITS] = {
463 [RLIMIT_CPU] = {"Max cpu time", "seconds"},
464 [RLIMIT_FSIZE] = {"Max file size", "bytes"},
465 [RLIMIT_DATA] = {"Max data size", "bytes"},
466 [RLIMIT_STACK] = {"Max stack size", "bytes"},
467 [RLIMIT_CORE] = {"Max core file size", "bytes"},
468 [RLIMIT_RSS] = {"Max resident set", "bytes"},
469 [RLIMIT_NPROC] = {"Max processes", "processes"},
470 [RLIMIT_NOFILE] = {"Max open files", "files"},
471 [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"},
472 [RLIMIT_AS] = {"Max address space", "bytes"},
473 [RLIMIT_LOCKS] = {"Max file locks", "locks"},
474 [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"},
475 [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"},
476 [RLIMIT_NICE] = {"Max nice priority", NULL},
477 [RLIMIT_RTPRIO] = {"Max realtime priority", NULL},
478 [RLIMIT_RTTIME] = {"Max realtime timeout", "us"},
479 };
480
481 /* Display limits for a process */
482 static int proc_pid_limits(struct task_struct *task, char *buffer)
483 {
484 unsigned int i;
485 int count = 0;
486 unsigned long flags;
487 char *bufptr = buffer;
488
489 struct rlimit rlim[RLIM_NLIMITS];
490
491 if (!lock_task_sighand(task, &flags))
492 return 0;
493 memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS);
494 unlock_task_sighand(task, &flags);
495
496 /*
497 * print the file header
498 */
499 count += sprintf(&bufptr[count], "%-25s %-20s %-20s %-10s\n",
500 "Limit", "Soft Limit", "Hard Limit", "Units");
501
502 for (i = 0; i < RLIM_NLIMITS; i++) {
503 if (rlim[i].rlim_cur == RLIM_INFINITY)
504 count += sprintf(&bufptr[count], "%-25s %-20s ",
505 lnames[i].name, "unlimited");
506 else
507 count += sprintf(&bufptr[count], "%-25s %-20lu ",
508 lnames[i].name, rlim[i].rlim_cur);
509
510 if (rlim[i].rlim_max == RLIM_INFINITY)
511 count += sprintf(&bufptr[count], "%-20s ", "unlimited");
512 else
513 count += sprintf(&bufptr[count], "%-20lu ",
514 rlim[i].rlim_max);
515
516 if (lnames[i].unit)
517 count += sprintf(&bufptr[count], "%-10s\n",
518 lnames[i].unit);
519 else
520 count += sprintf(&bufptr[count], "\n");
521 }
522
523 return count;
524 }
525
526 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
527 static int proc_pid_syscall(struct task_struct *task, char *buffer)
528 {
529 long nr;
530 unsigned long args[6], sp, pc;
531
532 if (task_current_syscall(task, &nr, args, 6, &sp, &pc))
533 return sprintf(buffer, "running\n");
534
535 if (nr < 0)
536 return sprintf(buffer, "%ld 0x%lx 0x%lx\n", nr, sp, pc);
537
538 return sprintf(buffer,
539 "%ld 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n",
540 nr,
541 args[0], args[1], args[2], args[3], args[4], args[5],
542 sp, pc);
543 }
544 #endif /* CONFIG_HAVE_ARCH_TRACEHOOK */
545
546 /************************************************************************/
547 /* Here the fs part begins */
548 /************************************************************************/
549
550 /* permission checks */
551 static int proc_fd_access_allowed(struct inode *inode)
552 {
553 struct task_struct *task;
554 int allowed = 0;
555 /* Allow access to a task's file descriptors if it is us or we
556 * may use ptrace attach to the process and find out that
557 * information.
558 */
559 task = get_proc_task(inode);
560 if (task) {
561 allowed = ptrace_may_access(task, PTRACE_MODE_READ);
562 put_task_struct(task);
563 }
564 return allowed;
565 }
566
567 static int proc_setattr(struct dentry *dentry, struct iattr *attr)
568 {
569 int error;
570 struct inode *inode = dentry->d_inode;
571
572 if (attr->ia_valid & ATTR_MODE)
573 return -EPERM;
574
575 error = inode_change_ok(inode, attr);
576 if (!error)
577 error = inode_setattr(inode, attr);
578 return error;
579 }
580
581 static const struct inode_operations proc_def_inode_operations = {
582 .setattr = proc_setattr,
583 };
584
585 static int mounts_open_common(struct inode *inode, struct file *file,
586 const struct seq_operations *op)
587 {
588 struct task_struct *task = get_proc_task(inode);
589 struct nsproxy *nsp;
590 struct mnt_namespace *ns = NULL;
591 struct path root;
592 struct proc_mounts *p;
593 int ret = -EINVAL;
594
595 if (task) {
596 rcu_read_lock();
597 nsp = task_nsproxy(task);
598 if (nsp) {
599 ns = nsp->mnt_ns;
600 if (ns)
601 get_mnt_ns(ns);
602 }
603 rcu_read_unlock();
604 if (ns && get_fs_path(task, &root, 1) == 0)
605 ret = 0;
606 put_task_struct(task);
607 }
608
609 if (!ns)
610 goto err;
611 if (ret)
612 goto err_put_ns;
613
614 ret = -ENOMEM;
615 p = kmalloc(sizeof(struct proc_mounts), GFP_KERNEL);
616 if (!p)
617 goto err_put_path;
618
619 file->private_data = &p->m;
620 ret = seq_open(file, op);
621 if (ret)
622 goto err_free;
623
624 p->m.private = p;
625 p->ns = ns;
626 p->root = root;
627 p->event = ns->event;
628
629 return 0;
630
631 err_free:
632 kfree(p);
633 err_put_path:
634 path_put(&root);
635 err_put_ns:
636 put_mnt_ns(ns);
637 err:
638 return ret;
639 }
640
641 static int mounts_release(struct inode *inode, struct file *file)
642 {
643 struct proc_mounts *p = file->private_data;
644 path_put(&p->root);
645 put_mnt_ns(p->ns);
646 return seq_release(inode, file);
647 }
648
649 static unsigned mounts_poll(struct file *file, poll_table *wait)
650 {
651 struct proc_mounts *p = file->private_data;
652 unsigned res = POLLIN | POLLRDNORM;
653
654 poll_wait(file, &p->ns->poll, wait);
655 if (mnt_had_events(p))
656 res |= POLLERR | POLLPRI;
657
658 return res;
659 }
660
661 static int mounts_open(struct inode *inode, struct file *file)
662 {
663 return mounts_open_common(inode, file, &mounts_op);
664 }
665
666 static const struct file_operations proc_mounts_operations = {
667 .open = mounts_open,
668 .read = seq_read,
669 .llseek = seq_lseek,
670 .release = mounts_release,
671 .poll = mounts_poll,
672 };
673
674 static int mountinfo_open(struct inode *inode, struct file *file)
675 {
676 return mounts_open_common(inode, file, &mountinfo_op);
677 }
678
679 static const struct file_operations proc_mountinfo_operations = {
680 .open = mountinfo_open,
681 .read = seq_read,
682 .llseek = seq_lseek,
683 .release = mounts_release,
684 .poll = mounts_poll,
685 };
686
687 static int mountstats_open(struct inode *inode, struct file *file)
688 {
689 return mounts_open_common(inode, file, &mountstats_op);
690 }
691
692 static const struct file_operations proc_mountstats_operations = {
693 .open = mountstats_open,
694 .read = seq_read,
695 .llseek = seq_lseek,
696 .release = mounts_release,
697 };
698
699 #define PROC_BLOCK_SIZE (3*1024) /* 4K page size but our output routines use some slack for overruns */
700
701 static ssize_t proc_info_read(struct file * file, char __user * buf,
702 size_t count, loff_t *ppos)
703 {
704 struct inode * inode = file->f_path.dentry->d_inode;
705 unsigned long page;
706 ssize_t length;
707 struct task_struct *task = get_proc_task(inode);
708
709 length = -ESRCH;
710 if (!task)
711 goto out_no_task;
712
713 if (count > PROC_BLOCK_SIZE)
714 count = PROC_BLOCK_SIZE;
715
716 length = -ENOMEM;
717 if (!(page = __get_free_page(GFP_TEMPORARY)))
718 goto out;
719
720 length = PROC_I(inode)->op.proc_read(task, (char*)page);
721
722 if (length >= 0)
723 length = simple_read_from_buffer(buf, count, ppos, (char *)page, length);
724 free_page(page);
725 out:
726 put_task_struct(task);
727 out_no_task:
728 return length;
729 }
730
731 static const struct file_operations proc_info_file_operations = {
732 .read = proc_info_read,
733 };
734
735 static int proc_single_show(struct seq_file *m, void *v)
736 {
737 struct inode *inode = m->private;
738 struct pid_namespace *ns;
739 struct pid *pid;
740 struct task_struct *task;
741 int ret;
742
743 ns = inode->i_sb->s_fs_info;
744 pid = proc_pid(inode);
745 task = get_pid_task(pid, PIDTYPE_PID);
746 if (!task)
747 return -ESRCH;
748
749 ret = PROC_I(inode)->op.proc_show(m, ns, pid, task);
750
751 put_task_struct(task);
752 return ret;
753 }
754
755 static int proc_single_open(struct inode *inode, struct file *filp)
756 {
757 int ret;
758 ret = single_open(filp, proc_single_show, NULL);
759 if (!ret) {
760 struct seq_file *m = filp->private_data;
761
762 m->private = inode;
763 }
764 return ret;
765 }
766
767 static const struct file_operations proc_single_file_operations = {
768 .open = proc_single_open,
769 .read = seq_read,
770 .llseek = seq_lseek,
771 .release = single_release,
772 };
773
774 static int mem_open(struct inode* inode, struct file* file)
775 {
776 file->private_data = (void*)((long)current->self_exec_id);
777 return 0;
778 }
779
780 static ssize_t mem_read(struct file * file, char __user * buf,
781 size_t count, loff_t *ppos)
782 {
783 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
784 char *page;
785 unsigned long src = *ppos;
786 int ret = -ESRCH;
787 struct mm_struct *mm;
788
789 if (!task)
790 goto out_no_task;
791
792 if (check_mem_permission(task))
793 goto out;
794
795 ret = -ENOMEM;
796 page = (char *)__get_free_page(GFP_TEMPORARY);
797 if (!page)
798 goto out;
799
800 ret = 0;
801
802 mm = get_task_mm(task);
803 if (!mm)
804 goto out_free;
805
806 ret = -EIO;
807
808 if (file->private_data != (void*)((long)current->self_exec_id))
809 goto out_put;
810
811 ret = 0;
812
813 while (count > 0) {
814 int this_len, retval;
815
816 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
817 retval = access_process_vm(task, src, page, this_len, 0);
818 if (!retval || check_mem_permission(task)) {
819 if (!ret)
820 ret = -EIO;
821 break;
822 }
823
824 if (copy_to_user(buf, page, retval)) {
825 ret = -EFAULT;
826 break;
827 }
828
829 ret += retval;
830 src += retval;
831 buf += retval;
832 count -= retval;
833 }
834 *ppos = src;
835
836 out_put:
837 mmput(mm);
838 out_free:
839 free_page((unsigned long) page);
840 out:
841 put_task_struct(task);
842 out_no_task:
843 return ret;
844 }
845
846 #define mem_write NULL
847
848 #ifndef mem_write
849 /* This is a security hazard */
850 static ssize_t mem_write(struct file * file, const char __user *buf,
851 size_t count, loff_t *ppos)
852 {
853 int copied;
854 char *page;
855 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
856 unsigned long dst = *ppos;
857
858 copied = -ESRCH;
859 if (!task)
860 goto out_no_task;
861
862 if (check_mem_permission(task))
863 goto out;
864
865 copied = -ENOMEM;
866 page = (char *)__get_free_page(GFP_TEMPORARY);
867 if (!page)
868 goto out;
869
870 copied = 0;
871 while (count > 0) {
872 int this_len, retval;
873
874 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
875 if (copy_from_user(page, buf, this_len)) {
876 copied = -EFAULT;
877 break;
878 }
879 retval = access_process_vm(task, dst, page, this_len, 1);
880 if (!retval) {
881 if (!copied)
882 copied = -EIO;
883 break;
884 }
885 copied += retval;
886 buf += retval;
887 dst += retval;
888 count -= retval;
889 }
890 *ppos = dst;
891 free_page((unsigned long) page);
892 out:
893 put_task_struct(task);
894 out_no_task:
895 return copied;
896 }
897 #endif
898
899 loff_t mem_lseek(struct file *file, loff_t offset, int orig)
900 {
901 switch (orig) {
902 case 0:
903 file->f_pos = offset;
904 break;
905 case 1:
906 file->f_pos += offset;
907 break;
908 default:
909 return -EINVAL;
910 }
911 force_successful_syscall_return();
912 return file->f_pos;
913 }
914
915 static const struct file_operations proc_mem_operations = {
916 .llseek = mem_lseek,
917 .read = mem_read,
918 .write = mem_write,
919 .open = mem_open,
920 };
921
922 static ssize_t environ_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_dentry->d_inode);
926 char *page;
927 unsigned long src = *ppos;
928 int ret = -ESRCH;
929 struct mm_struct *mm;
930
931 if (!task)
932 goto out_no_task;
933
934 if (!ptrace_may_access(task, PTRACE_MODE_READ))
935 goto out;
936
937 ret = -ENOMEM;
938 page = (char *)__get_free_page(GFP_TEMPORARY);
939 if (!page)
940 goto out;
941
942 ret = 0;
943
944 mm = get_task_mm(task);
945 if (!mm)
946 goto out_free;
947
948 while (count > 0) {
949 int this_len, retval, max_len;
950
951 this_len = mm->env_end - (mm->env_start + src);
952
953 if (this_len <= 0)
954 break;
955
956 max_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
957 this_len = (this_len > max_len) ? max_len : this_len;
958
959 retval = access_process_vm(task, (mm->env_start + src),
960 page, this_len, 0);
961
962 if (retval <= 0) {
963 ret = retval;
964 break;
965 }
966
967 if (copy_to_user(buf, page, retval)) {
968 ret = -EFAULT;
969 break;
970 }
971
972 ret += retval;
973 src += retval;
974 buf += retval;
975 count -= retval;
976 }
977 *ppos = src;
978
979 mmput(mm);
980 out_free:
981 free_page((unsigned long) page);
982 out:
983 put_task_struct(task);
984 out_no_task:
985 return ret;
986 }
987
988 static const struct file_operations proc_environ_operations = {
989 .read = environ_read,
990 };
991
992 static ssize_t oom_adjust_read(struct file *file, char __user *buf,
993 size_t count, loff_t *ppos)
994 {
995 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
996 char buffer[PROC_NUMBUF];
997 size_t len;
998 int oom_adjust = OOM_DISABLE;
999 unsigned long flags;
1000
1001 if (!task)
1002 return -ESRCH;
1003
1004 if (lock_task_sighand(task, &flags)) {
1005 oom_adjust = task->signal->oom_adj;
1006 unlock_task_sighand(task, &flags);
1007 }
1008
1009 put_task_struct(task);
1010
1011 len = snprintf(buffer, sizeof(buffer), "%i\n", oom_adjust);
1012
1013 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1014 }
1015
1016 static ssize_t oom_adjust_write(struct file *file, const char __user *buf,
1017 size_t count, loff_t *ppos)
1018 {
1019 struct task_struct *task;
1020 char buffer[PROC_NUMBUF];
1021 long oom_adjust;
1022 unsigned long flags;
1023 int err;
1024
1025 memset(buffer, 0, sizeof(buffer));
1026 if (count > sizeof(buffer) - 1)
1027 count = sizeof(buffer) - 1;
1028 if (copy_from_user(buffer, buf, count))
1029 return -EFAULT;
1030
1031 err = strict_strtol(strstrip(buffer), 0, &oom_adjust);
1032 if (err)
1033 return -EINVAL;
1034 if ((oom_adjust < OOM_ADJUST_MIN || oom_adjust > OOM_ADJUST_MAX) &&
1035 oom_adjust != OOM_DISABLE)
1036 return -EINVAL;
1037
1038 task = get_proc_task(file->f_path.dentry->d_inode);
1039 if (!task)
1040 return -ESRCH;
1041 if (!lock_task_sighand(task, &flags)) {
1042 put_task_struct(task);
1043 return -ESRCH;
1044 }
1045
1046 if (oom_adjust < task->signal->oom_adj && !capable(CAP_SYS_RESOURCE)) {
1047 unlock_task_sighand(task, &flags);
1048 put_task_struct(task);
1049 return -EACCES;
1050 }
1051
1052 task->signal->oom_adj = oom_adjust;
1053
1054 unlock_task_sighand(task, &flags);
1055 put_task_struct(task);
1056
1057 return count;
1058 }
1059
1060 static const struct file_operations proc_oom_adjust_operations = {
1061 .read = oom_adjust_read,
1062 .write = oom_adjust_write,
1063 };
1064
1065 #ifdef CONFIG_AUDITSYSCALL
1066 #define TMPBUFLEN 21
1067 static ssize_t proc_loginuid_read(struct file * file, char __user * buf,
1068 size_t count, loff_t *ppos)
1069 {
1070 struct inode * inode = file->f_path.dentry->d_inode;
1071 struct task_struct *task = get_proc_task(inode);
1072 ssize_t length;
1073 char tmpbuf[TMPBUFLEN];
1074
1075 if (!task)
1076 return -ESRCH;
1077 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1078 audit_get_loginuid(task));
1079 put_task_struct(task);
1080 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1081 }
1082
1083 static ssize_t proc_loginuid_write(struct file * file, const char __user * buf,
1084 size_t count, loff_t *ppos)
1085 {
1086 struct inode * inode = file->f_path.dentry->d_inode;
1087 char *page, *tmp;
1088 ssize_t length;
1089 uid_t loginuid;
1090
1091 if (!capable(CAP_AUDIT_CONTROL))
1092 return -EPERM;
1093
1094 rcu_read_lock();
1095 if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) {
1096 rcu_read_unlock();
1097 return -EPERM;
1098 }
1099 rcu_read_unlock();
1100
1101 if (count >= PAGE_SIZE)
1102 count = PAGE_SIZE - 1;
1103
1104 if (*ppos != 0) {
1105 /* No partial writes. */
1106 return -EINVAL;
1107 }
1108 page = (char*)__get_free_page(GFP_TEMPORARY);
1109 if (!page)
1110 return -ENOMEM;
1111 length = -EFAULT;
1112 if (copy_from_user(page, buf, count))
1113 goto out_free_page;
1114
1115 page[count] = '\0';
1116 loginuid = simple_strtoul(page, &tmp, 10);
1117 if (tmp == page) {
1118 length = -EINVAL;
1119 goto out_free_page;
1120
1121 }
1122 length = audit_set_loginuid(current, loginuid);
1123 if (likely(length == 0))
1124 length = count;
1125
1126 out_free_page:
1127 free_page((unsigned long) page);
1128 return length;
1129 }
1130
1131 static const struct file_operations proc_loginuid_operations = {
1132 .read = proc_loginuid_read,
1133 .write = proc_loginuid_write,
1134 };
1135
1136 static ssize_t proc_sessionid_read(struct file * file, char __user * buf,
1137 size_t count, loff_t *ppos)
1138 {
1139 struct inode * inode = file->f_path.dentry->d_inode;
1140 struct task_struct *task = get_proc_task(inode);
1141 ssize_t length;
1142 char tmpbuf[TMPBUFLEN];
1143
1144 if (!task)
1145 return -ESRCH;
1146 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1147 audit_get_sessionid(task));
1148 put_task_struct(task);
1149 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1150 }
1151
1152 static const struct file_operations proc_sessionid_operations = {
1153 .read = proc_sessionid_read,
1154 };
1155 #endif
1156
1157 #ifdef CONFIG_FAULT_INJECTION
1158 static ssize_t proc_fault_inject_read(struct file * file, char __user * buf,
1159 size_t count, loff_t *ppos)
1160 {
1161 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
1162 char buffer[PROC_NUMBUF];
1163 size_t len;
1164 int make_it_fail;
1165
1166 if (!task)
1167 return -ESRCH;
1168 make_it_fail = task->make_it_fail;
1169 put_task_struct(task);
1170
1171 len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail);
1172
1173 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1174 }
1175
1176 static ssize_t proc_fault_inject_write(struct file * file,
1177 const char __user * buf, size_t count, loff_t *ppos)
1178 {
1179 struct task_struct *task;
1180 char buffer[PROC_NUMBUF], *end;
1181 int make_it_fail;
1182
1183 if (!capable(CAP_SYS_RESOURCE))
1184 return -EPERM;
1185 memset(buffer, 0, sizeof(buffer));
1186 if (count > sizeof(buffer) - 1)
1187 count = sizeof(buffer) - 1;
1188 if (copy_from_user(buffer, buf, count))
1189 return -EFAULT;
1190 make_it_fail = simple_strtol(strstrip(buffer), &end, 0);
1191 if (*end)
1192 return -EINVAL;
1193 task = get_proc_task(file->f_dentry->d_inode);
1194 if (!task)
1195 return -ESRCH;
1196 task->make_it_fail = make_it_fail;
1197 put_task_struct(task);
1198
1199 return count;
1200 }
1201
1202 static const struct file_operations proc_fault_inject_operations = {
1203 .read = proc_fault_inject_read,
1204 .write = proc_fault_inject_write,
1205 };
1206 #endif
1207
1208
1209 #ifdef CONFIG_SCHED_DEBUG
1210 /*
1211 * Print out various scheduling related per-task fields:
1212 */
1213 static int sched_show(struct seq_file *m, void *v)
1214 {
1215 struct inode *inode = m->private;
1216 struct task_struct *p;
1217
1218 p = get_proc_task(inode);
1219 if (!p)
1220 return -ESRCH;
1221 proc_sched_show_task(p, m);
1222
1223 put_task_struct(p);
1224
1225 return 0;
1226 }
1227
1228 static ssize_t
1229 sched_write(struct file *file, const char __user *buf,
1230 size_t count, loff_t *offset)
1231 {
1232 struct inode *inode = file->f_path.dentry->d_inode;
1233 struct task_struct *p;
1234
1235 p = get_proc_task(inode);
1236 if (!p)
1237 return -ESRCH;
1238 proc_sched_set_task(p);
1239
1240 put_task_struct(p);
1241
1242 return count;
1243 }
1244
1245 static int sched_open(struct inode *inode, struct file *filp)
1246 {
1247 int ret;
1248
1249 ret = single_open(filp, sched_show, NULL);
1250 if (!ret) {
1251 struct seq_file *m = filp->private_data;
1252
1253 m->private = inode;
1254 }
1255 return ret;
1256 }
1257
1258 static const struct file_operations proc_pid_sched_operations = {
1259 .open = sched_open,
1260 .read = seq_read,
1261 .write = sched_write,
1262 .llseek = seq_lseek,
1263 .release = single_release,
1264 };
1265
1266 #endif
1267
1268 static ssize_t comm_write(struct file *file, const char __user *buf,
1269 size_t count, loff_t *offset)
1270 {
1271 struct inode *inode = file->f_path.dentry->d_inode;
1272 struct task_struct *p;
1273 char buffer[TASK_COMM_LEN];
1274
1275 memset(buffer, 0, sizeof(buffer));
1276 if (count > sizeof(buffer) - 1)
1277 count = sizeof(buffer) - 1;
1278 if (copy_from_user(buffer, buf, count))
1279 return -EFAULT;
1280
1281 p = get_proc_task(inode);
1282 if (!p)
1283 return -ESRCH;
1284
1285 if (same_thread_group(current, p))
1286 set_task_comm(p, buffer);
1287 else
1288 count = -EINVAL;
1289
1290 put_task_struct(p);
1291
1292 return count;
1293 }
1294
1295 static int comm_show(struct seq_file *m, void *v)
1296 {
1297 struct inode *inode = m->private;
1298 struct task_struct *p;
1299
1300 p = get_proc_task(inode);
1301 if (!p)
1302 return -ESRCH;
1303
1304 task_lock(p);
1305 seq_printf(m, "%s\n", p->comm);
1306 task_unlock(p);
1307
1308 put_task_struct(p);
1309
1310 return 0;
1311 }
1312
1313 static int comm_open(struct inode *inode, struct file *filp)
1314 {
1315 int ret;
1316
1317 ret = single_open(filp, comm_show, NULL);
1318 if (!ret) {
1319 struct seq_file *m = filp->private_data;
1320
1321 m->private = inode;
1322 }
1323 return ret;
1324 }
1325
1326 static const struct file_operations proc_pid_set_comm_operations = {
1327 .open = comm_open,
1328 .read = seq_read,
1329 .write = comm_write,
1330 .llseek = seq_lseek,
1331 .release = single_release,
1332 };
1333
1334 /*
1335 * We added or removed a vma mapping the executable. The vmas are only mapped
1336 * during exec and are not mapped with the mmap system call.
1337 * Callers must hold down_write() on the mm's mmap_sem for these
1338 */
1339 void added_exe_file_vma(struct mm_struct *mm)
1340 {
1341 mm->num_exe_file_vmas++;
1342 }
1343
1344 void removed_exe_file_vma(struct mm_struct *mm)
1345 {
1346 mm->num_exe_file_vmas--;
1347 if ((mm->num_exe_file_vmas == 0) && mm->exe_file){
1348 fput(mm->exe_file);
1349 mm->exe_file = NULL;
1350 }
1351
1352 }
1353
1354 void set_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file)
1355 {
1356 if (new_exe_file)
1357 get_file(new_exe_file);
1358 if (mm->exe_file)
1359 fput(mm->exe_file);
1360 mm->exe_file = new_exe_file;
1361 mm->num_exe_file_vmas = 0;
1362 }
1363
1364 struct file *get_mm_exe_file(struct mm_struct *mm)
1365 {
1366 struct file *exe_file;
1367
1368 /* We need mmap_sem to protect against races with removal of
1369 * VM_EXECUTABLE vmas */
1370 down_read(&mm->mmap_sem);
1371 exe_file = mm->exe_file;
1372 if (exe_file)
1373 get_file(exe_file);
1374 up_read(&mm->mmap_sem);
1375 return exe_file;
1376 }
1377
1378 void dup_mm_exe_file(struct mm_struct *oldmm, struct mm_struct *newmm)
1379 {
1380 /* It's safe to write the exe_file pointer without exe_file_lock because
1381 * this is called during fork when the task is not yet in /proc */
1382 newmm->exe_file = get_mm_exe_file(oldmm);
1383 }
1384
1385 static int proc_exe_link(struct inode *inode, struct path *exe_path)
1386 {
1387 struct task_struct *task;
1388 struct mm_struct *mm;
1389 struct file *exe_file;
1390
1391 task = get_proc_task(inode);
1392 if (!task)
1393 return -ENOENT;
1394 mm = get_task_mm(task);
1395 put_task_struct(task);
1396 if (!mm)
1397 return -ENOENT;
1398 exe_file = get_mm_exe_file(mm);
1399 mmput(mm);
1400 if (exe_file) {
1401 *exe_path = exe_file->f_path;
1402 path_get(&exe_file->f_path);
1403 fput(exe_file);
1404 return 0;
1405 } else
1406 return -ENOENT;
1407 }
1408
1409 static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd)
1410 {
1411 struct inode *inode = dentry->d_inode;
1412 int error = -EACCES;
1413
1414 /* We don't need a base pointer in the /proc filesystem */
1415 path_put(&nd->path);
1416
1417 /* Are we allowed to snoop on the tasks file descriptors? */
1418 if (!proc_fd_access_allowed(inode))
1419 goto out;
1420
1421 error = PROC_I(inode)->op.proc_get_link(inode, &nd->path);
1422 out:
1423 return ERR_PTR(error);
1424 }
1425
1426 static int do_proc_readlink(struct path *path, char __user *buffer, int buflen)
1427 {
1428 char *tmp = (char*)__get_free_page(GFP_TEMPORARY);
1429 char *pathname;
1430 int len;
1431
1432 if (!tmp)
1433 return -ENOMEM;
1434
1435 pathname = d_path(path, tmp, PAGE_SIZE);
1436 len = PTR_ERR(pathname);
1437 if (IS_ERR(pathname))
1438 goto out;
1439 len = tmp + PAGE_SIZE - 1 - pathname;
1440
1441 if (len > buflen)
1442 len = buflen;
1443 if (copy_to_user(buffer, pathname, len))
1444 len = -EFAULT;
1445 out:
1446 free_page((unsigned long)tmp);
1447 return len;
1448 }
1449
1450 static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen)
1451 {
1452 int error = -EACCES;
1453 struct inode *inode = dentry->d_inode;
1454 struct path path;
1455
1456 /* Are we allowed to snoop on the tasks file descriptors? */
1457 if (!proc_fd_access_allowed(inode))
1458 goto out;
1459
1460 error = PROC_I(inode)->op.proc_get_link(inode, &path);
1461 if (error)
1462 goto out;
1463
1464 error = do_proc_readlink(&path, buffer, buflen);
1465 path_put(&path);
1466 out:
1467 return error;
1468 }
1469
1470 static const struct inode_operations proc_pid_link_inode_operations = {
1471 .readlink = proc_pid_readlink,
1472 .follow_link = proc_pid_follow_link,
1473 .setattr = proc_setattr,
1474 };
1475
1476
1477 /* building an inode */
1478
1479 static int task_dumpable(struct task_struct *task)
1480 {
1481 int dumpable = 0;
1482 struct mm_struct *mm;
1483
1484 task_lock(task);
1485 mm = task->mm;
1486 if (mm)
1487 dumpable = get_dumpable(mm);
1488 task_unlock(task);
1489 if(dumpable == 1)
1490 return 1;
1491 return 0;
1492 }
1493
1494
1495 static struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task)
1496 {
1497 struct inode * inode;
1498 struct proc_inode *ei;
1499 const struct cred *cred;
1500
1501 /* We need a new inode */
1502
1503 inode = new_inode(sb);
1504 if (!inode)
1505 goto out;
1506
1507 /* Common stuff */
1508 ei = PROC_I(inode);
1509 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
1510 inode->i_op = &proc_def_inode_operations;
1511
1512 /*
1513 * grab the reference to task.
1514 */
1515 ei->pid = get_task_pid(task, PIDTYPE_PID);
1516 if (!ei->pid)
1517 goto out_unlock;
1518
1519 if (task_dumpable(task)) {
1520 rcu_read_lock();
1521 cred = __task_cred(task);
1522 inode->i_uid = cred->euid;
1523 inode->i_gid = cred->egid;
1524 rcu_read_unlock();
1525 }
1526 security_task_to_inode(task, inode);
1527
1528 out:
1529 return inode;
1530
1531 out_unlock:
1532 iput(inode);
1533 return NULL;
1534 }
1535
1536 static int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
1537 {
1538 struct inode *inode = dentry->d_inode;
1539 struct task_struct *task;
1540 const struct cred *cred;
1541
1542 generic_fillattr(inode, stat);
1543
1544 rcu_read_lock();
1545 stat->uid = 0;
1546 stat->gid = 0;
1547 task = pid_task(proc_pid(inode), PIDTYPE_PID);
1548 if (task) {
1549 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
1550 task_dumpable(task)) {
1551 cred = __task_cred(task);
1552 stat->uid = cred->euid;
1553 stat->gid = cred->egid;
1554 }
1555 }
1556 rcu_read_unlock();
1557 return 0;
1558 }
1559
1560 /* dentry stuff */
1561
1562 /*
1563 * Exceptional case: normally we are not allowed to unhash a busy
1564 * directory. In this case, however, we can do it - no aliasing problems
1565 * due to the way we treat inodes.
1566 *
1567 * Rewrite the inode's ownerships here because the owning task may have
1568 * performed a setuid(), etc.
1569 *
1570 * Before the /proc/pid/status file was created the only way to read
1571 * the effective uid of a /process was to stat /proc/pid. Reading
1572 * /proc/pid/status is slow enough that procps and other packages
1573 * kept stating /proc/pid. To keep the rules in /proc simple I have
1574 * made this apply to all per process world readable and executable
1575 * directories.
1576 */
1577 static int pid_revalidate(struct dentry *dentry, struct nameidata *nd)
1578 {
1579 struct inode *inode = dentry->d_inode;
1580 struct task_struct *task = get_proc_task(inode);
1581 const struct cred *cred;
1582
1583 if (task) {
1584 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
1585 task_dumpable(task)) {
1586 rcu_read_lock();
1587 cred = __task_cred(task);
1588 inode->i_uid = cred->euid;
1589 inode->i_gid = cred->egid;
1590 rcu_read_unlock();
1591 } else {
1592 inode->i_uid = 0;
1593 inode->i_gid = 0;
1594 }
1595 inode->i_mode &= ~(S_ISUID | S_ISGID);
1596 security_task_to_inode(task, inode);
1597 put_task_struct(task);
1598 return 1;
1599 }
1600 d_drop(dentry);
1601 return 0;
1602 }
1603
1604 static int pid_delete_dentry(struct dentry * dentry)
1605 {
1606 /* Is the task we represent dead?
1607 * If so, then don't put the dentry on the lru list,
1608 * kill it immediately.
1609 */
1610 return !proc_pid(dentry->d_inode)->tasks[PIDTYPE_PID].first;
1611 }
1612
1613 static const struct dentry_operations pid_dentry_operations =
1614 {
1615 .d_revalidate = pid_revalidate,
1616 .d_delete = pid_delete_dentry,
1617 };
1618
1619 /* Lookups */
1620
1621 typedef struct dentry *instantiate_t(struct inode *, struct dentry *,
1622 struct task_struct *, const void *);
1623
1624 /*
1625 * Fill a directory entry.
1626 *
1627 * If possible create the dcache entry and derive our inode number and
1628 * file type from dcache entry.
1629 *
1630 * Since all of the proc inode numbers are dynamically generated, the inode
1631 * numbers do not exist until the inode is cache. This means creating the
1632 * the dcache entry in readdir is necessary to keep the inode numbers
1633 * reported by readdir in sync with the inode numbers reported
1634 * by stat.
1635 */
1636 static int proc_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
1637 char *name, int len,
1638 instantiate_t instantiate, struct task_struct *task, const void *ptr)
1639 {
1640 struct dentry *child, *dir = filp->f_path.dentry;
1641 struct inode *inode;
1642 struct qstr qname;
1643 ino_t ino = 0;
1644 unsigned type = DT_UNKNOWN;
1645
1646 qname.name = name;
1647 qname.len = len;
1648 qname.hash = full_name_hash(name, len);
1649
1650 child = d_lookup(dir, &qname);
1651 if (!child) {
1652 struct dentry *new;
1653 new = d_alloc(dir, &qname);
1654 if (new) {
1655 child = instantiate(dir->d_inode, new, task, ptr);
1656 if (child)
1657 dput(new);
1658 else
1659 child = new;
1660 }
1661 }
1662 if (!child || IS_ERR(child) || !child->d_inode)
1663 goto end_instantiate;
1664 inode = child->d_inode;
1665 if (inode) {
1666 ino = inode->i_ino;
1667 type = inode->i_mode >> 12;
1668 }
1669 dput(child);
1670 end_instantiate:
1671 if (!ino)
1672 ino = find_inode_number(dir, &qname);
1673 if (!ino)
1674 ino = 1;
1675 return filldir(dirent, name, len, filp->f_pos, ino, type);
1676 }
1677
1678 static unsigned name_to_int(struct dentry *dentry)
1679 {
1680 const char *name = dentry->d_name.name;
1681 int len = dentry->d_name.len;
1682 unsigned n = 0;
1683
1684 if (len > 1 && *name == '0')
1685 goto out;
1686 while (len-- > 0) {
1687 unsigned c = *name++ - '0';
1688 if (c > 9)
1689 goto out;
1690 if (n >= (~0U-9)/10)
1691 goto out;
1692 n *= 10;
1693 n += c;
1694 }
1695 return n;
1696 out:
1697 return ~0U;
1698 }
1699
1700 #define PROC_FDINFO_MAX 64
1701
1702 static int proc_fd_info(struct inode *inode, struct path *path, char *info)
1703 {
1704 struct task_struct *task = get_proc_task(inode);
1705 struct files_struct *files = NULL;
1706 struct file *file;
1707 int fd = proc_fd(inode);
1708
1709 if (task) {
1710 files = get_files_struct(task);
1711 put_task_struct(task);
1712 }
1713 if (files) {
1714 /*
1715 * We are not taking a ref to the file structure, so we must
1716 * hold ->file_lock.
1717 */
1718 spin_lock(&files->file_lock);
1719 file = fcheck_files(files, fd);
1720 if (file) {
1721 if (path) {
1722 *path = file->f_path;
1723 path_get(&file->f_path);
1724 }
1725 if (info)
1726 snprintf(info, PROC_FDINFO_MAX,
1727 "pos:\t%lli\n"
1728 "flags:\t0%o\n",
1729 (long long) file->f_pos,
1730 file->f_flags);
1731 spin_unlock(&files->file_lock);
1732 put_files_struct(files);
1733 return 0;
1734 }
1735 spin_unlock(&files->file_lock);
1736 put_files_struct(files);
1737 }
1738 return -ENOENT;
1739 }
1740
1741 static int proc_fd_link(struct inode *inode, struct path *path)
1742 {
1743 return proc_fd_info(inode, path, NULL);
1744 }
1745
1746 static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
1747 {
1748 struct inode *inode = dentry->d_inode;
1749 struct task_struct *task = get_proc_task(inode);
1750 int fd = proc_fd(inode);
1751 struct files_struct *files;
1752 const struct cred *cred;
1753
1754 if (task) {
1755 files = get_files_struct(task);
1756 if (files) {
1757 rcu_read_lock();
1758 if (fcheck_files(files, fd)) {
1759 rcu_read_unlock();
1760 put_files_struct(files);
1761 if (task_dumpable(task)) {
1762 rcu_read_lock();
1763 cred = __task_cred(task);
1764 inode->i_uid = cred->euid;
1765 inode->i_gid = cred->egid;
1766 rcu_read_unlock();
1767 } else {
1768 inode->i_uid = 0;
1769 inode->i_gid = 0;
1770 }
1771 inode->i_mode &= ~(S_ISUID | S_ISGID);
1772 security_task_to_inode(task, inode);
1773 put_task_struct(task);
1774 return 1;
1775 }
1776 rcu_read_unlock();
1777 put_files_struct(files);
1778 }
1779 put_task_struct(task);
1780 }
1781 d_drop(dentry);
1782 return 0;
1783 }
1784
1785 static const struct dentry_operations tid_fd_dentry_operations =
1786 {
1787 .d_revalidate = tid_fd_revalidate,
1788 .d_delete = pid_delete_dentry,
1789 };
1790
1791 static struct dentry *proc_fd_instantiate(struct inode *dir,
1792 struct dentry *dentry, struct task_struct *task, const void *ptr)
1793 {
1794 unsigned fd = *(const unsigned *)ptr;
1795 struct file *file;
1796 struct files_struct *files;
1797 struct inode *inode;
1798 struct proc_inode *ei;
1799 struct dentry *error = ERR_PTR(-ENOENT);
1800
1801 inode = proc_pid_make_inode(dir->i_sb, task);
1802 if (!inode)
1803 goto out;
1804 ei = PROC_I(inode);
1805 ei->fd = fd;
1806 files = get_files_struct(task);
1807 if (!files)
1808 goto out_iput;
1809 inode->i_mode = S_IFLNK;
1810
1811 /*
1812 * We are not taking a ref to the file structure, so we must
1813 * hold ->file_lock.
1814 */
1815 spin_lock(&files->file_lock);
1816 file = fcheck_files(files, fd);
1817 if (!file)
1818 goto out_unlock;
1819 if (file->f_mode & FMODE_READ)
1820 inode->i_mode |= S_IRUSR | S_IXUSR;
1821 if (file->f_mode & FMODE_WRITE)
1822 inode->i_mode |= S_IWUSR | S_IXUSR;
1823 spin_unlock(&files->file_lock);
1824 put_files_struct(files);
1825
1826 inode->i_op = &proc_pid_link_inode_operations;
1827 inode->i_size = 64;
1828 ei->op.proc_get_link = proc_fd_link;
1829 dentry->d_op = &tid_fd_dentry_operations;
1830 d_add(dentry, inode);
1831 /* Close the race of the process dying before we return the dentry */
1832 if (tid_fd_revalidate(dentry, NULL))
1833 error = NULL;
1834
1835 out:
1836 return error;
1837 out_unlock:
1838 spin_unlock(&files->file_lock);
1839 put_files_struct(files);
1840 out_iput:
1841 iput(inode);
1842 goto out;
1843 }
1844
1845 static struct dentry *proc_lookupfd_common(struct inode *dir,
1846 struct dentry *dentry,
1847 instantiate_t instantiate)
1848 {
1849 struct task_struct *task = get_proc_task(dir);
1850 unsigned fd = name_to_int(dentry);
1851 struct dentry *result = ERR_PTR(-ENOENT);
1852
1853 if (!task)
1854 goto out_no_task;
1855 if (fd == ~0U)
1856 goto out;
1857
1858 result = instantiate(dir, dentry, task, &fd);
1859 out:
1860 put_task_struct(task);
1861 out_no_task:
1862 return result;
1863 }
1864
1865 static int proc_readfd_common(struct file * filp, void * dirent,
1866 filldir_t filldir, instantiate_t instantiate)
1867 {
1868 struct dentry *dentry = filp->f_path.dentry;
1869 struct inode *inode = dentry->d_inode;
1870 struct task_struct *p = get_proc_task(inode);
1871 unsigned int fd, ino;
1872 int retval;
1873 struct files_struct * files;
1874
1875 retval = -ENOENT;
1876 if (!p)
1877 goto out_no_task;
1878 retval = 0;
1879
1880 fd = filp->f_pos;
1881 switch (fd) {
1882 case 0:
1883 if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0)
1884 goto out;
1885 filp->f_pos++;
1886 case 1:
1887 ino = parent_ino(dentry);
1888 if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0)
1889 goto out;
1890 filp->f_pos++;
1891 default:
1892 files = get_files_struct(p);
1893 if (!files)
1894 goto out;
1895 rcu_read_lock();
1896 for (fd = filp->f_pos-2;
1897 fd < files_fdtable(files)->max_fds;
1898 fd++, filp->f_pos++) {
1899 char name[PROC_NUMBUF];
1900 int len;
1901
1902 if (!fcheck_files(files, fd))
1903 continue;
1904 rcu_read_unlock();
1905
1906 len = snprintf(name, sizeof(name), "%d", fd);
1907 if (proc_fill_cache(filp, dirent, filldir,
1908 name, len, instantiate,
1909 p, &fd) < 0) {
1910 rcu_read_lock();
1911 break;
1912 }
1913 rcu_read_lock();
1914 }
1915 rcu_read_unlock();
1916 put_files_struct(files);
1917 }
1918 out:
1919 put_task_struct(p);
1920 out_no_task:
1921 return retval;
1922 }
1923
1924 static struct dentry *proc_lookupfd(struct inode *dir, struct dentry *dentry,
1925 struct nameidata *nd)
1926 {
1927 return proc_lookupfd_common(dir, dentry, proc_fd_instantiate);
1928 }
1929
1930 static int proc_readfd(struct file *filp, void *dirent, filldir_t filldir)
1931 {
1932 return proc_readfd_common(filp, dirent, filldir, proc_fd_instantiate);
1933 }
1934
1935 static ssize_t proc_fdinfo_read(struct file *file, char __user *buf,
1936 size_t len, loff_t *ppos)
1937 {
1938 char tmp[PROC_FDINFO_MAX];
1939 int err = proc_fd_info(file->f_path.dentry->d_inode, NULL, tmp);
1940 if (!err)
1941 err = simple_read_from_buffer(buf, len, ppos, tmp, strlen(tmp));
1942 return err;
1943 }
1944
1945 static const struct file_operations proc_fdinfo_file_operations = {
1946 .open = nonseekable_open,
1947 .read = proc_fdinfo_read,
1948 };
1949
1950 static const struct file_operations proc_fd_operations = {
1951 .read = generic_read_dir,
1952 .readdir = proc_readfd,
1953 };
1954
1955 /*
1956 * /proc/pid/fd needs a special permission handler so that a process can still
1957 * access /proc/self/fd after it has executed a setuid().
1958 */
1959 static int proc_fd_permission(struct inode *inode, int mask)
1960 {
1961 int rv;
1962
1963 rv = generic_permission(inode, mask, NULL);
1964 if (rv == 0)
1965 return 0;
1966 if (task_pid(current) == proc_pid(inode))
1967 rv = 0;
1968 return rv;
1969 }
1970
1971 /*
1972 * proc directories can do almost nothing..
1973 */
1974 static const struct inode_operations proc_fd_inode_operations = {
1975 .lookup = proc_lookupfd,
1976 .permission = proc_fd_permission,
1977 .setattr = proc_setattr,
1978 };
1979
1980 static struct dentry *proc_fdinfo_instantiate(struct inode *dir,
1981 struct dentry *dentry, struct task_struct *task, const void *ptr)
1982 {
1983 unsigned fd = *(unsigned *)ptr;
1984 struct inode *inode;
1985 struct proc_inode *ei;
1986 struct dentry *error = ERR_PTR(-ENOENT);
1987
1988 inode = proc_pid_make_inode(dir->i_sb, task);
1989 if (!inode)
1990 goto out;
1991 ei = PROC_I(inode);
1992 ei->fd = fd;
1993 inode->i_mode = S_IFREG | S_IRUSR;
1994 inode->i_fop = &proc_fdinfo_file_operations;
1995 dentry->d_op = &tid_fd_dentry_operations;
1996 d_add(dentry, inode);
1997 /* Close the race of the process dying before we return the dentry */
1998 if (tid_fd_revalidate(dentry, NULL))
1999 error = NULL;
2000
2001 out:
2002 return error;
2003 }
2004
2005 static struct dentry *proc_lookupfdinfo(struct inode *dir,
2006 struct dentry *dentry,
2007 struct nameidata *nd)
2008 {
2009 return proc_lookupfd_common(dir, dentry, proc_fdinfo_instantiate);
2010 }
2011
2012 static int proc_readfdinfo(struct file *filp, void *dirent, filldir_t filldir)
2013 {
2014 return proc_readfd_common(filp, dirent, filldir,
2015 proc_fdinfo_instantiate);
2016 }
2017
2018 static const struct file_operations proc_fdinfo_operations = {
2019 .read = generic_read_dir,
2020 .readdir = proc_readfdinfo,
2021 };
2022
2023 /*
2024 * proc directories can do almost nothing..
2025 */
2026 static const struct inode_operations proc_fdinfo_inode_operations = {
2027 .lookup = proc_lookupfdinfo,
2028 .setattr = proc_setattr,
2029 };
2030
2031
2032 static struct dentry *proc_pident_instantiate(struct inode *dir,
2033 struct dentry *dentry, struct task_struct *task, const void *ptr)
2034 {
2035 const struct pid_entry *p = ptr;
2036 struct inode *inode;
2037 struct proc_inode *ei;
2038 struct dentry *error = ERR_PTR(-ENOENT);
2039
2040 inode = proc_pid_make_inode(dir->i_sb, task);
2041 if (!inode)
2042 goto out;
2043
2044 ei = PROC_I(inode);
2045 inode->i_mode = p->mode;
2046 if (S_ISDIR(inode->i_mode))
2047 inode->i_nlink = 2; /* Use getattr to fix if necessary */
2048 if (p->iop)
2049 inode->i_op = p->iop;
2050 if (p->fop)
2051 inode->i_fop = p->fop;
2052 ei->op = p->op;
2053 dentry->d_op = &pid_dentry_operations;
2054 d_add(dentry, inode);
2055 /* Close the race of the process dying before we return the dentry */
2056 if (pid_revalidate(dentry, NULL))
2057 error = NULL;
2058 out:
2059 return error;
2060 }
2061
2062 static struct dentry *proc_pident_lookup(struct inode *dir,
2063 struct dentry *dentry,
2064 const struct pid_entry *ents,
2065 unsigned int nents)
2066 {
2067 struct dentry *error;
2068 struct task_struct *task = get_proc_task(dir);
2069 const struct pid_entry *p, *last;
2070
2071 error = ERR_PTR(-ENOENT);
2072
2073 if (!task)
2074 goto out_no_task;
2075
2076 /*
2077 * Yes, it does not scale. And it should not. Don't add
2078 * new entries into /proc/<tgid>/ without very good reasons.
2079 */
2080 last = &ents[nents - 1];
2081 for (p = ents; p <= last; p++) {
2082 if (p->len != dentry->d_name.len)
2083 continue;
2084 if (!memcmp(dentry->d_name.name, p->name, p->len))
2085 break;
2086 }
2087 if (p > last)
2088 goto out;
2089
2090 error = proc_pident_instantiate(dir, dentry, task, p);
2091 out:
2092 put_task_struct(task);
2093 out_no_task:
2094 return error;
2095 }
2096
2097 static int proc_pident_fill_cache(struct file *filp, void *dirent,
2098 filldir_t filldir, struct task_struct *task, const struct pid_entry *p)
2099 {
2100 return proc_fill_cache(filp, dirent, filldir, p->name, p->len,
2101 proc_pident_instantiate, task, p);
2102 }
2103
2104 static int proc_pident_readdir(struct file *filp,
2105 void *dirent, filldir_t filldir,
2106 const struct pid_entry *ents, unsigned int nents)
2107 {
2108 int i;
2109 struct dentry *dentry = filp->f_path.dentry;
2110 struct inode *inode = dentry->d_inode;
2111 struct task_struct *task = get_proc_task(inode);
2112 const struct pid_entry *p, *last;
2113 ino_t ino;
2114 int ret;
2115
2116 ret = -ENOENT;
2117 if (!task)
2118 goto out_no_task;
2119
2120 ret = 0;
2121 i = filp->f_pos;
2122 switch (i) {
2123 case 0:
2124 ino = inode->i_ino;
2125 if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0)
2126 goto out;
2127 i++;
2128 filp->f_pos++;
2129 /* fall through */
2130 case 1:
2131 ino = parent_ino(dentry);
2132 if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0)
2133 goto out;
2134 i++;
2135 filp->f_pos++;
2136 /* fall through */
2137 default:
2138 i -= 2;
2139 if (i >= nents) {
2140 ret = 1;
2141 goto out;
2142 }
2143 p = ents + i;
2144 last = &ents[nents - 1];
2145 while (p <= last) {
2146 if (proc_pident_fill_cache(filp, dirent, filldir, task, p) < 0)
2147 goto out;
2148 filp->f_pos++;
2149 p++;
2150 }
2151 }
2152
2153 ret = 1;
2154 out:
2155 put_task_struct(task);
2156 out_no_task:
2157 return ret;
2158 }
2159
2160 #ifdef CONFIG_SECURITY
2161 static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,
2162 size_t count, loff_t *ppos)
2163 {
2164 struct inode * inode = file->f_path.dentry->d_inode;
2165 char *p = NULL;
2166 ssize_t length;
2167 struct task_struct *task = get_proc_task(inode);
2168
2169 if (!task)
2170 return -ESRCH;
2171
2172 length = security_getprocattr(task,
2173 (char*)file->f_path.dentry->d_name.name,
2174 &p);
2175 put_task_struct(task);
2176 if (length > 0)
2177 length = simple_read_from_buffer(buf, count, ppos, p, length);
2178 kfree(p);
2179 return length;
2180 }
2181
2182 static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
2183 size_t count, loff_t *ppos)
2184 {
2185 struct inode * inode = file->f_path.dentry->d_inode;
2186 char *page;
2187 ssize_t length;
2188 struct task_struct *task = get_proc_task(inode);
2189
2190 length = -ESRCH;
2191 if (!task)
2192 goto out_no_task;
2193 if (count > PAGE_SIZE)
2194 count = PAGE_SIZE;
2195
2196 /* No partial writes. */
2197 length = -EINVAL;
2198 if (*ppos != 0)
2199 goto out;
2200
2201 length = -ENOMEM;
2202 page = (char*)__get_free_page(GFP_TEMPORARY);
2203 if (!page)
2204 goto out;
2205
2206 length = -EFAULT;
2207 if (copy_from_user(page, buf, count))
2208 goto out_free;
2209
2210 /* Guard against adverse ptrace interaction */
2211 length = mutex_lock_interruptible(&task->cred_guard_mutex);
2212 if (length < 0)
2213 goto out_free;
2214
2215 length = security_setprocattr(task,
2216 (char*)file->f_path.dentry->d_name.name,
2217 (void*)page, count);
2218 mutex_unlock(&task->cred_guard_mutex);
2219 out_free:
2220 free_page((unsigned long) page);
2221 out:
2222 put_task_struct(task);
2223 out_no_task:
2224 return length;
2225 }
2226
2227 static const struct file_operations proc_pid_attr_operations = {
2228 .read = proc_pid_attr_read,
2229 .write = proc_pid_attr_write,
2230 };
2231
2232 static const struct pid_entry attr_dir_stuff[] = {
2233 REG("current", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2234 REG("prev", S_IRUGO, proc_pid_attr_operations),
2235 REG("exec", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2236 REG("fscreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2237 REG("keycreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2238 REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2239 };
2240
2241 static int proc_attr_dir_readdir(struct file * filp,
2242 void * dirent, filldir_t filldir)
2243 {
2244 return proc_pident_readdir(filp,dirent,filldir,
2245 attr_dir_stuff,ARRAY_SIZE(attr_dir_stuff));
2246 }
2247
2248 static const struct file_operations proc_attr_dir_operations = {
2249 .read = generic_read_dir,
2250 .readdir = proc_attr_dir_readdir,
2251 };
2252
2253 static struct dentry *proc_attr_dir_lookup(struct inode *dir,
2254 struct dentry *dentry, struct nameidata *nd)
2255 {
2256 return proc_pident_lookup(dir, dentry,
2257 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
2258 }
2259
2260 static const struct inode_operations proc_attr_dir_inode_operations = {
2261 .lookup = proc_attr_dir_lookup,
2262 .getattr = pid_getattr,
2263 .setattr = proc_setattr,
2264 };
2265
2266 #endif
2267
2268 #ifdef CONFIG_ELF_CORE
2269 static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf,
2270 size_t count, loff_t *ppos)
2271 {
2272 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
2273 struct mm_struct *mm;
2274 char buffer[PROC_NUMBUF];
2275 size_t len;
2276 int ret;
2277
2278 if (!task)
2279 return -ESRCH;
2280
2281 ret = 0;
2282 mm = get_task_mm(task);
2283 if (mm) {
2284 len = snprintf(buffer, sizeof(buffer), "%08lx\n",
2285 ((mm->flags & MMF_DUMP_FILTER_MASK) >>
2286 MMF_DUMP_FILTER_SHIFT));
2287 mmput(mm);
2288 ret = simple_read_from_buffer(buf, count, ppos, buffer, len);
2289 }
2290
2291 put_task_struct(task);
2292
2293 return ret;
2294 }
2295
2296 static ssize_t proc_coredump_filter_write(struct file *file,
2297 const char __user *buf,
2298 size_t count,
2299 loff_t *ppos)
2300 {
2301 struct task_struct *task;
2302 struct mm_struct *mm;
2303 char buffer[PROC_NUMBUF], *end;
2304 unsigned int val;
2305 int ret;
2306 int i;
2307 unsigned long mask;
2308
2309 ret = -EFAULT;
2310 memset(buffer, 0, sizeof(buffer));
2311 if (count > sizeof(buffer) - 1)
2312 count = sizeof(buffer) - 1;
2313 if (copy_from_user(buffer, buf, count))
2314 goto out_no_task;
2315
2316 ret = -EINVAL;
2317 val = (unsigned int)simple_strtoul(buffer, &end, 0);
2318 if (*end == '\n')
2319 end++;
2320 if (end - buffer == 0)
2321 goto out_no_task;
2322
2323 ret = -ESRCH;
2324 task = get_proc_task(file->f_dentry->d_inode);
2325 if (!task)
2326 goto out_no_task;
2327
2328 ret = end - buffer;
2329 mm = get_task_mm(task);
2330 if (!mm)
2331 goto out_no_mm;
2332
2333 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) {
2334 if (val & mask)
2335 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2336 else
2337 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2338 }
2339
2340 mmput(mm);
2341 out_no_mm:
2342 put_task_struct(task);
2343 out_no_task:
2344 return ret;
2345 }
2346
2347 static const struct file_operations proc_coredump_filter_operations = {
2348 .read = proc_coredump_filter_read,
2349 .write = proc_coredump_filter_write,
2350 };
2351 #endif
2352
2353 /*
2354 * /proc/self:
2355 */
2356 static int proc_self_readlink(struct dentry *dentry, char __user *buffer,
2357 int buflen)
2358 {
2359 struct pid_namespace *ns = dentry->d_sb->s_fs_info;
2360 pid_t tgid = task_tgid_nr_ns(current, ns);
2361 char tmp[PROC_NUMBUF];
2362 if (!tgid)
2363 return -ENOENT;
2364 sprintf(tmp, "%d", tgid);
2365 return vfs_readlink(dentry,buffer,buflen,tmp);
2366 }
2367
2368 static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd)
2369 {
2370 struct pid_namespace *ns = dentry->d_sb->s_fs_info;
2371 pid_t tgid = task_tgid_nr_ns(current, ns);
2372 char *name = ERR_PTR(-ENOENT);
2373 if (tgid) {
2374 name = __getname();
2375 if (!name)
2376 name = ERR_PTR(-ENOMEM);
2377 else
2378 sprintf(name, "%d", tgid);
2379 }
2380 nd_set_link(nd, name);
2381 return NULL;
2382 }
2383
2384 static void proc_self_put_link(struct dentry *dentry, struct nameidata *nd,
2385 void *cookie)
2386 {
2387 char *s = nd_get_link(nd);
2388 if (!IS_ERR(s))
2389 __putname(s);
2390 }
2391
2392 static const struct inode_operations proc_self_inode_operations = {
2393 .readlink = proc_self_readlink,
2394 .follow_link = proc_self_follow_link,
2395 .put_link = proc_self_put_link,
2396 };
2397
2398 /*
2399 * proc base
2400 *
2401 * These are the directory entries in the root directory of /proc
2402 * that properly belong to the /proc filesystem, as they describe
2403 * describe something that is process related.
2404 */
2405 static const struct pid_entry proc_base_stuff[] = {
2406 NOD("self", S_IFLNK|S_IRWXUGO,
2407 &proc_self_inode_operations, NULL, {}),
2408 };
2409
2410 /*
2411 * Exceptional case: normally we are not allowed to unhash a busy
2412 * directory. In this case, however, we can do it - no aliasing problems
2413 * due to the way we treat inodes.
2414 */
2415 static int proc_base_revalidate(struct dentry *dentry, struct nameidata *nd)
2416 {
2417 struct inode *inode = dentry->d_inode;
2418 struct task_struct *task = get_proc_task(inode);
2419 if (task) {
2420 put_task_struct(task);
2421 return 1;
2422 }
2423 d_drop(dentry);
2424 return 0;
2425 }
2426
2427 static const struct dentry_operations proc_base_dentry_operations =
2428 {
2429 .d_revalidate = proc_base_revalidate,
2430 .d_delete = pid_delete_dentry,
2431 };
2432
2433 static struct dentry *proc_base_instantiate(struct inode *dir,
2434 struct dentry *dentry, struct task_struct *task, const void *ptr)
2435 {
2436 const struct pid_entry *p = ptr;
2437 struct inode *inode;
2438 struct proc_inode *ei;
2439 struct dentry *error = ERR_PTR(-EINVAL);
2440
2441 /* Allocate the inode */
2442 error = ERR_PTR(-ENOMEM);
2443 inode = new_inode(dir->i_sb);
2444 if (!inode)
2445 goto out;
2446
2447 /* Initialize the inode */
2448 ei = PROC_I(inode);
2449 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
2450
2451 /*
2452 * grab the reference to the task.
2453 */
2454 ei->pid = get_task_pid(task, PIDTYPE_PID);
2455 if (!ei->pid)
2456 goto out_iput;
2457
2458 inode->i_mode = p->mode;
2459 if (S_ISDIR(inode->i_mode))
2460 inode->i_nlink = 2;
2461 if (S_ISLNK(inode->i_mode))
2462 inode->i_size = 64;
2463 if (p->iop)
2464 inode->i_op = p->iop;
2465 if (p->fop)
2466 inode->i_fop = p->fop;
2467 ei->op = p->op;
2468 dentry->d_op = &proc_base_dentry_operations;
2469 d_add(dentry, inode);
2470 error = NULL;
2471 out:
2472 return error;
2473 out_iput:
2474 iput(inode);
2475 goto out;
2476 }
2477
2478 static struct dentry *proc_base_lookup(struct inode *dir, struct dentry *dentry)
2479 {
2480 struct dentry *error;
2481 struct task_struct *task = get_proc_task(dir);
2482 const struct pid_entry *p, *last;
2483
2484 error = ERR_PTR(-ENOENT);
2485
2486 if (!task)
2487 goto out_no_task;
2488
2489 /* Lookup the directory entry */
2490 last = &proc_base_stuff[ARRAY_SIZE(proc_base_stuff) - 1];
2491 for (p = proc_base_stuff; p <= last; p++) {
2492 if (p->len != dentry->d_name.len)
2493 continue;
2494 if (!memcmp(dentry->d_name.name, p->name, p->len))
2495 break;
2496 }
2497 if (p > last)
2498 goto out;
2499
2500 error = proc_base_instantiate(dir, dentry, task, p);
2501
2502 out:
2503 put_task_struct(task);
2504 out_no_task:
2505 return error;
2506 }
2507
2508 static int proc_base_fill_cache(struct file *filp, void *dirent,
2509 filldir_t filldir, struct task_struct *task, const struct pid_entry *p)
2510 {
2511 return proc_fill_cache(filp, dirent, filldir, p->name, p->len,
2512 proc_base_instantiate, task, p);
2513 }
2514
2515 #ifdef CONFIG_TASK_IO_ACCOUNTING
2516 static int do_io_accounting(struct task_struct *task, char *buffer, int whole)
2517 {
2518 struct task_io_accounting acct = task->ioac;
2519 unsigned long flags;
2520
2521 if (whole && lock_task_sighand(task, &flags)) {
2522 struct task_struct *t = task;
2523
2524 task_io_accounting_add(&acct, &task->signal->ioac);
2525 while_each_thread(task, t)
2526 task_io_accounting_add(&acct, &t->ioac);
2527
2528 unlock_task_sighand(task, &flags);
2529 }
2530 return sprintf(buffer,
2531 "rchar: %llu\n"
2532 "wchar: %llu\n"
2533 "syscr: %llu\n"
2534 "syscw: %llu\n"
2535 "read_bytes: %llu\n"
2536 "write_bytes: %llu\n"
2537 "cancelled_write_bytes: %llu\n",
2538 (unsigned long long)acct.rchar,
2539 (unsigned long long)acct.wchar,
2540 (unsigned long long)acct.syscr,
2541 (unsigned long long)acct.syscw,
2542 (unsigned long long)acct.read_bytes,
2543 (unsigned long long)acct.write_bytes,
2544 (unsigned long long)acct.cancelled_write_bytes);
2545 }
2546
2547 static int proc_tid_io_accounting(struct task_struct *task, char *buffer)
2548 {
2549 return do_io_accounting(task, buffer, 0);
2550 }
2551
2552 static int proc_tgid_io_accounting(struct task_struct *task, char *buffer)
2553 {
2554 return do_io_accounting(task, buffer, 1);
2555 }
2556 #endif /* CONFIG_TASK_IO_ACCOUNTING */
2557
2558 static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns,
2559 struct pid *pid, struct task_struct *task)
2560 {
2561 seq_printf(m, "%08x\n", task->personality);
2562 return 0;
2563 }
2564
2565 /*
2566 * Thread groups
2567 */
2568 static const struct file_operations proc_task_operations;
2569 static const struct inode_operations proc_task_inode_operations;
2570
2571 static const struct pid_entry tgid_base_stuff[] = {
2572 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations),
2573 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
2574 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
2575 #ifdef CONFIG_NET
2576 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),
2577 #endif
2578 REG("environ", S_IRUSR, proc_environ_operations),
2579 INF("auxv", S_IRUSR, proc_pid_auxv),
2580 ONE("status", S_IRUGO, proc_pid_status),
2581 ONE("personality", S_IRUSR, proc_pid_personality),
2582 INF("limits", S_IRUSR, proc_pid_limits),
2583 #ifdef CONFIG_SCHED_DEBUG
2584 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
2585 #endif
2586 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
2587 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
2588 INF("syscall", S_IRUSR, proc_pid_syscall),
2589 #endif
2590 INF("cmdline", S_IRUGO, proc_pid_cmdline),
2591 ONE("stat", S_IRUGO, proc_tgid_stat),
2592 ONE("statm", S_IRUGO, proc_pid_statm),
2593 REG("maps", S_IRUGO, proc_maps_operations),
2594 #ifdef CONFIG_NUMA
2595 REG("numa_maps", S_IRUGO, proc_numa_maps_operations),
2596 #endif
2597 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
2598 LNK("cwd", proc_cwd_link),
2599 LNK("root", proc_root_link),
2600 LNK("exe", proc_exe_link),
2601 REG("mounts", S_IRUGO, proc_mounts_operations),
2602 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
2603 REG("mountstats", S_IRUSR, proc_mountstats_operations),
2604 #ifdef CONFIG_PROC_PAGE_MONITOR
2605 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
2606 REG("smaps", S_IRUGO, proc_smaps_operations),
2607 REG("pagemap", S_IRUSR, proc_pagemap_operations),
2608 #endif
2609 #ifdef CONFIG_SECURITY
2610 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
2611 #endif
2612 #ifdef CONFIG_KALLSYMS
2613 INF("wchan", S_IRUGO, proc_pid_wchan),
2614 #endif
2615 #ifdef CONFIG_STACKTRACE
2616 ONE("stack", S_IRUSR, proc_pid_stack),
2617 #endif
2618 #ifdef CONFIG_SCHEDSTATS
2619 INF("schedstat", S_IRUGO, proc_pid_schedstat),
2620 #endif
2621 #ifdef CONFIG_LATENCYTOP
2622 REG("latency", S_IRUGO, proc_lstats_operations),
2623 #endif
2624 #ifdef CONFIG_PROC_PID_CPUSET
2625 REG("cpuset", S_IRUGO, proc_cpuset_operations),
2626 #endif
2627 #ifdef CONFIG_CGROUPS
2628 REG("cgroup", S_IRUGO, proc_cgroup_operations),
2629 #endif
2630 INF("oom_score", S_IRUGO, proc_oom_score),
2631 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adjust_operations),
2632 #ifdef CONFIG_AUDITSYSCALL
2633 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
2634 REG("sessionid", S_IRUGO, proc_sessionid_operations),
2635 #endif
2636 #ifdef CONFIG_FAULT_INJECTION
2637 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
2638 #endif
2639 #ifdef CONFIG_ELF_CORE
2640 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations),
2641 #endif
2642 #ifdef CONFIG_TASK_IO_ACCOUNTING
2643 INF("io", S_IRUGO, proc_tgid_io_accounting),
2644 #endif
2645 };
2646
2647 static int proc_tgid_base_readdir(struct file * filp,
2648 void * dirent, filldir_t filldir)
2649 {
2650 return proc_pident_readdir(filp,dirent,filldir,
2651 tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff));
2652 }
2653
2654 static const struct file_operations proc_tgid_base_operations = {
2655 .read = generic_read_dir,
2656 .readdir = proc_tgid_base_readdir,
2657 };
2658
2659 static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
2660 return proc_pident_lookup(dir, dentry,
2661 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
2662 }
2663
2664 static const struct inode_operations proc_tgid_base_inode_operations = {
2665 .lookup = proc_tgid_base_lookup,
2666 .getattr = pid_getattr,
2667 .setattr = proc_setattr,
2668 };
2669
2670 static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid)
2671 {
2672 struct dentry *dentry, *leader, *dir;
2673 char buf[PROC_NUMBUF];
2674 struct qstr name;
2675
2676 name.name = buf;
2677 name.len = snprintf(buf, sizeof(buf), "%d", pid);
2678 dentry = d_hash_and_lookup(mnt->mnt_root, &name);
2679 if (dentry) {
2680 shrink_dcache_parent(dentry);
2681 d_drop(dentry);
2682 dput(dentry);
2683 }
2684
2685 name.name = buf;
2686 name.len = snprintf(buf, sizeof(buf), "%d", tgid);
2687 leader = d_hash_and_lookup(mnt->mnt_root, &name);
2688 if (!leader)
2689 goto out;
2690
2691 name.name = "task";
2692 name.len = strlen(name.name);
2693 dir = d_hash_and_lookup(leader, &name);
2694 if (!dir)
2695 goto out_put_leader;
2696
2697 name.name = buf;
2698 name.len = snprintf(buf, sizeof(buf), "%d", pid);
2699 dentry = d_hash_and_lookup(dir, &name);
2700 if (dentry) {
2701 shrink_dcache_parent(dentry);
2702 d_drop(dentry);
2703 dput(dentry);
2704 }
2705
2706 dput(dir);
2707 out_put_leader:
2708 dput(leader);
2709 out:
2710 return;
2711 }
2712
2713 /**
2714 * proc_flush_task - Remove dcache entries for @task from the /proc dcache.
2715 * @task: task that should be flushed.
2716 *
2717 * When flushing dentries from proc, one needs to flush them from global
2718 * proc (proc_mnt) and from all the namespaces' procs this task was seen
2719 * in. This call is supposed to do all of this job.
2720 *
2721 * Looks in the dcache for
2722 * /proc/@pid
2723 * /proc/@tgid/task/@pid
2724 * if either directory is present flushes it and all of it'ts children
2725 * from the dcache.
2726 *
2727 * It is safe and reasonable to cache /proc entries for a task until
2728 * that task exits. After that they just clog up the dcache with
2729 * useless entries, possibly causing useful dcache entries to be
2730 * flushed instead. This routine is proved to flush those useless
2731 * dcache entries at process exit time.
2732 *
2733 * NOTE: This routine is just an optimization so it does not guarantee
2734 * that no dcache entries will exist at process exit time it
2735 * just makes it very unlikely that any will persist.
2736 */
2737
2738 void proc_flush_task(struct task_struct *task)
2739 {
2740 int i;
2741 struct pid *pid, *tgid;
2742 struct upid *upid;
2743
2744 pid = task_pid(task);
2745 tgid = task_tgid(task);
2746
2747 for (i = 0; i <= pid->level; i++) {
2748 upid = &pid->numbers[i];
2749 proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr,
2750 tgid->numbers[i].nr);
2751 }
2752
2753 upid = &pid->numbers[pid->level];
2754 if (upid->nr == 1)
2755 pid_ns_release_proc(upid->ns);
2756 }
2757
2758 static struct dentry *proc_pid_instantiate(struct inode *dir,
2759 struct dentry * dentry,
2760 struct task_struct *task, const void *ptr)
2761 {
2762 struct dentry *error = ERR_PTR(-ENOENT);
2763 struct inode *inode;
2764
2765 inode = proc_pid_make_inode(dir->i_sb, task);
2766 if (!inode)
2767 goto out;
2768
2769 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
2770 inode->i_op = &proc_tgid_base_inode_operations;
2771 inode->i_fop = &proc_tgid_base_operations;
2772 inode->i_flags|=S_IMMUTABLE;
2773
2774 inode->i_nlink = 2 + pid_entry_count_dirs(tgid_base_stuff,
2775 ARRAY_SIZE(tgid_base_stuff));
2776
2777 dentry->d_op = &pid_dentry_operations;
2778
2779 d_add(dentry, inode);
2780 /* Close the race of the process dying before we return the dentry */
2781 if (pid_revalidate(dentry, NULL))
2782 error = NULL;
2783 out:
2784 return error;
2785 }
2786
2787 struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
2788 {
2789 struct dentry *result = ERR_PTR(-ENOENT);
2790 struct task_struct *task;
2791 unsigned tgid;
2792 struct pid_namespace *ns;
2793
2794 result = proc_base_lookup(dir, dentry);
2795 if (!IS_ERR(result) || PTR_ERR(result) != -ENOENT)
2796 goto out;
2797
2798 tgid = name_to_int(dentry);
2799 if (tgid == ~0U)
2800 goto out;
2801
2802 ns = dentry->d_sb->s_fs_info;
2803 rcu_read_lock();
2804 task = find_task_by_pid_ns(tgid, ns);
2805 if (task)
2806 get_task_struct(task);
2807 rcu_read_unlock();
2808 if (!task)
2809 goto out;
2810
2811 result = proc_pid_instantiate(dir, dentry, task, NULL);
2812 put_task_struct(task);
2813 out:
2814 return result;
2815 }
2816
2817 /*
2818 * Find the first task with tgid >= tgid
2819 *
2820 */
2821 struct tgid_iter {
2822 unsigned int tgid;
2823 struct task_struct *task;
2824 };
2825 static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter)
2826 {
2827 struct pid *pid;
2828
2829 if (iter.task)
2830 put_task_struct(iter.task);
2831 rcu_read_lock();
2832 retry:
2833 iter.task = NULL;
2834 pid = find_ge_pid(iter.tgid, ns);
2835 if (pid) {
2836 iter.tgid = pid_nr_ns(pid, ns);
2837 iter.task = pid_task(pid, PIDTYPE_PID);
2838 /* What we to know is if the pid we have find is the
2839 * pid of a thread_group_leader. Testing for task
2840 * being a thread_group_leader is the obvious thing
2841 * todo but there is a window when it fails, due to
2842 * the pid transfer logic in de_thread.
2843 *
2844 * So we perform the straight forward test of seeing
2845 * if the pid we have found is the pid of a thread
2846 * group leader, and don't worry if the task we have
2847 * found doesn't happen to be a thread group leader.
2848 * As we don't care in the case of readdir.
2849 */
2850 if (!iter.task || !has_group_leader_pid(iter.task)) {
2851 iter.tgid += 1;
2852 goto retry;
2853 }
2854 get_task_struct(iter.task);
2855 }
2856 rcu_read_unlock();
2857 return iter;
2858 }
2859
2860 #define TGID_OFFSET (FIRST_PROCESS_ENTRY + ARRAY_SIZE(proc_base_stuff))
2861
2862 static int proc_pid_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
2863 struct tgid_iter iter)
2864 {
2865 char name[PROC_NUMBUF];
2866 int len = snprintf(name, sizeof(name), "%d", iter.tgid);
2867 return proc_fill_cache(filp, dirent, filldir, name, len,
2868 proc_pid_instantiate, iter.task, NULL);
2869 }
2870
2871 /* for the /proc/ directory itself, after non-process stuff has been done */
2872 int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir)
2873 {
2874 unsigned int nr = filp->f_pos - FIRST_PROCESS_ENTRY;
2875 struct task_struct *reaper = get_proc_task(filp->f_path.dentry->d_inode);
2876 struct tgid_iter iter;
2877 struct pid_namespace *ns;
2878
2879 if (!reaper)
2880 goto out_no_task;
2881
2882 for (; nr < ARRAY_SIZE(proc_base_stuff); filp->f_pos++, nr++) {
2883 const struct pid_entry *p = &proc_base_stuff[nr];
2884 if (proc_base_fill_cache(filp, dirent, filldir, reaper, p) < 0)
2885 goto out;
2886 }
2887
2888 ns = filp->f_dentry->d_sb->s_fs_info;
2889 iter.task = NULL;
2890 iter.tgid = filp->f_pos - TGID_OFFSET;
2891 for (iter = next_tgid(ns, iter);
2892 iter.task;
2893 iter.tgid += 1, iter = next_tgid(ns, iter)) {
2894 filp->f_pos = iter.tgid + TGID_OFFSET;
2895 if (proc_pid_fill_cache(filp, dirent, filldir, iter) < 0) {
2896 put_task_struct(iter.task);
2897 goto out;
2898 }
2899 }
2900 filp->f_pos = PID_MAX_LIMIT + TGID_OFFSET;
2901 out:
2902 put_task_struct(reaper);
2903 out_no_task:
2904 return 0;
2905 }
2906
2907 /*
2908 * Tasks
2909 */
2910 static const struct pid_entry tid_base_stuff[] = {
2911 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
2912 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
2913 REG("environ", S_IRUSR, proc_environ_operations),
2914 INF("auxv", S_IRUSR, proc_pid_auxv),
2915 ONE("status", S_IRUGO, proc_pid_status),
2916 ONE("personality", S_IRUSR, proc_pid_personality),
2917 INF("limits", S_IRUSR, proc_pid_limits),
2918 #ifdef CONFIG_SCHED_DEBUG
2919 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
2920 #endif
2921 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
2922 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
2923 INF("syscall", S_IRUSR, proc_pid_syscall),
2924 #endif
2925 INF("cmdline", S_IRUGO, proc_pid_cmdline),
2926 ONE("stat", S_IRUGO, proc_tid_stat),
2927 ONE("statm", S_IRUGO, proc_pid_statm),
2928 REG("maps", S_IRUGO, proc_maps_operations),
2929 #ifdef CONFIG_NUMA
2930 REG("numa_maps", S_IRUGO, proc_numa_maps_operations),
2931 #endif
2932 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
2933 LNK("cwd", proc_cwd_link),
2934 LNK("root", proc_root_link),
2935 LNK("exe", proc_exe_link),
2936 REG("mounts", S_IRUGO, proc_mounts_operations),
2937 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
2938 #ifdef CONFIG_PROC_PAGE_MONITOR
2939 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
2940 REG("smaps", S_IRUGO, proc_smaps_operations),
2941 REG("pagemap", S_IRUSR, proc_pagemap_operations),
2942 #endif
2943 #ifdef CONFIG_SECURITY
2944 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
2945 #endif
2946 #ifdef CONFIG_KALLSYMS
2947 INF("wchan", S_IRUGO, proc_pid_wchan),
2948 #endif
2949 #ifdef CONFIG_STACKTRACE
2950 ONE("stack", S_IRUSR, proc_pid_stack),
2951 #endif
2952 #ifdef CONFIG_SCHEDSTATS
2953 INF("schedstat", S_IRUGO, proc_pid_schedstat),
2954 #endif
2955 #ifdef CONFIG_LATENCYTOP
2956 REG("latency", S_IRUGO, proc_lstats_operations),
2957 #endif
2958 #ifdef CONFIG_PROC_PID_CPUSET
2959 REG("cpuset", S_IRUGO, proc_cpuset_operations),
2960 #endif
2961 #ifdef CONFIG_CGROUPS
2962 REG("cgroup", S_IRUGO, proc_cgroup_operations),
2963 #endif
2964 INF("oom_score", S_IRUGO, proc_oom_score),
2965 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adjust_operations),
2966 #ifdef CONFIG_AUDITSYSCALL
2967 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
2968 REG("sessionid", S_IRUSR, proc_sessionid_operations),
2969 #endif
2970 #ifdef CONFIG_FAULT_INJECTION
2971 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
2972 #endif
2973 #ifdef CONFIG_TASK_IO_ACCOUNTING
2974 INF("io", S_IRUGO, proc_tid_io_accounting),
2975 #endif
2976 };
2977
2978 static int proc_tid_base_readdir(struct file * filp,
2979 void * dirent, filldir_t filldir)
2980 {
2981 return proc_pident_readdir(filp,dirent,filldir,
2982 tid_base_stuff,ARRAY_SIZE(tid_base_stuff));
2983 }
2984
2985 static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
2986 return proc_pident_lookup(dir, dentry,
2987 tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
2988 }
2989
2990 static const struct file_operations proc_tid_base_operations = {
2991 .read = generic_read_dir,
2992 .readdir = proc_tid_base_readdir,
2993 };
2994
2995 static const struct inode_operations proc_tid_base_inode_operations = {
2996 .lookup = proc_tid_base_lookup,
2997 .getattr = pid_getattr,
2998 .setattr = proc_setattr,
2999 };
3000
3001 static struct dentry *proc_task_instantiate(struct inode *dir,
3002 struct dentry *dentry, struct task_struct *task, const void *ptr)
3003 {
3004 struct dentry *error = ERR_PTR(-ENOENT);
3005 struct inode *inode;
3006 inode = proc_pid_make_inode(dir->i_sb, task);
3007
3008 if (!inode)
3009 goto out;
3010 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
3011 inode->i_op = &proc_tid_base_inode_operations;
3012 inode->i_fop = &proc_tid_base_operations;
3013 inode->i_flags|=S_IMMUTABLE;
3014
3015 inode->i_nlink = 2 + pid_entry_count_dirs(tid_base_stuff,
3016 ARRAY_SIZE(tid_base_stuff));
3017
3018 dentry->d_op = &pid_dentry_operations;
3019
3020 d_add(dentry, inode);
3021 /* Close the race of the process dying before we return the dentry */
3022 if (pid_revalidate(dentry, NULL))
3023 error = NULL;
3024 out:
3025 return error;
3026 }
3027
3028 static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
3029 {
3030 struct dentry *result = ERR_PTR(-ENOENT);
3031 struct task_struct *task;
3032 struct task_struct *leader = get_proc_task(dir);
3033 unsigned tid;
3034 struct pid_namespace *ns;
3035
3036 if (!leader)
3037 goto out_no_task;
3038
3039 tid = name_to_int(dentry);
3040 if (tid == ~0U)
3041 goto out;
3042
3043 ns = dentry->d_sb->s_fs_info;
3044 rcu_read_lock();
3045 task = find_task_by_pid_ns(tid, ns);
3046 if (task)
3047 get_task_struct(task);
3048 rcu_read_unlock();
3049 if (!task)
3050 goto out;
3051 if (!same_thread_group(leader, task))
3052 goto out_drop_task;
3053
3054 result = proc_task_instantiate(dir, dentry, task, NULL);
3055 out_drop_task:
3056 put_task_struct(task);
3057 out:
3058 put_task_struct(leader);
3059 out_no_task:
3060 return result;
3061 }
3062
3063 /*
3064 * Find the first tid of a thread group to return to user space.
3065 *
3066 * Usually this is just the thread group leader, but if the users
3067 * buffer was too small or there was a seek into the middle of the
3068 * directory we have more work todo.
3069 *
3070 * In the case of a short read we start with find_task_by_pid.
3071 *
3072 * In the case of a seek we start with the leader and walk nr
3073 * threads past it.
3074 */
3075 static struct task_struct *first_tid(struct task_struct *leader,
3076 int tid, int nr, struct pid_namespace *ns)
3077 {
3078 struct task_struct *pos;
3079
3080 rcu_read_lock();
3081 /* Attempt to start with the pid of a thread */
3082 if (tid && (nr > 0)) {
3083 pos = find_task_by_pid_ns(tid, ns);
3084 if (pos && (pos->group_leader == leader))
3085 goto found;
3086 }
3087
3088 /* If nr exceeds the number of threads there is nothing todo */
3089 pos = NULL;
3090 if (nr && nr >= get_nr_threads(leader))
3091 goto out;
3092
3093 /* If we haven't found our starting place yet start
3094 * with the leader and walk nr threads forward.
3095 */
3096 for (pos = leader; nr > 0; --nr) {
3097 pos = next_thread(pos);
3098 if (pos == leader) {
3099 pos = NULL;
3100 goto out;
3101 }
3102 }
3103 found:
3104 get_task_struct(pos);
3105 out:
3106 rcu_read_unlock();
3107 return pos;
3108 }
3109
3110 /*
3111 * Find the next thread in the thread list.
3112 * Return NULL if there is an error or no next thread.
3113 *
3114 * The reference to the input task_struct is released.
3115 */
3116 static struct task_struct *next_tid(struct task_struct *start)
3117 {
3118 struct task_struct *pos = NULL;
3119 rcu_read_lock();
3120 if (pid_alive(start)) {
3121 pos = next_thread(start);
3122 if (thread_group_leader(pos))
3123 pos = NULL;
3124 else
3125 get_task_struct(pos);
3126 }
3127 rcu_read_unlock();
3128 put_task_struct(start);
3129 return pos;
3130 }
3131
3132 static int proc_task_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
3133 struct task_struct *task, int tid)
3134 {
3135 char name[PROC_NUMBUF];
3136 int len = snprintf(name, sizeof(name), "%d", tid);
3137 return proc_fill_cache(filp, dirent, filldir, name, len,
3138 proc_task_instantiate, task, NULL);
3139 }
3140
3141 /* for the /proc/TGID/task/ directories */
3142 static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir)
3143 {
3144 struct dentry *dentry = filp->f_path.dentry;
3145 struct inode *inode = dentry->d_inode;
3146 struct task_struct *leader = NULL;
3147 struct task_struct *task;
3148 int retval = -ENOENT;
3149 ino_t ino;
3150 int tid;
3151 struct pid_namespace *ns;
3152
3153 task = get_proc_task(inode);
3154 if (!task)
3155 goto out_no_task;
3156 rcu_read_lock();
3157 if (pid_alive(task)) {
3158 leader = task->group_leader;
3159 get_task_struct(leader);
3160 }
3161 rcu_read_unlock();
3162 put_task_struct(task);
3163 if (!leader)
3164 goto out_no_task;
3165 retval = 0;
3166
3167 switch ((unsigned long)filp->f_pos) {
3168 case 0:
3169 ino = inode->i_ino;
3170 if (filldir(dirent, ".", 1, filp->f_pos, ino, DT_DIR) < 0)
3171 goto out;
3172 filp->f_pos++;
3173 /* fall through */
3174 case 1:
3175 ino = parent_ino(dentry);
3176 if (filldir(dirent, "..", 2, filp->f_pos, ino, DT_DIR) < 0)
3177 goto out;
3178 filp->f_pos++;
3179 /* fall through */
3180 }
3181
3182 /* f_version caches the tgid value that the last readdir call couldn't
3183 * return. lseek aka telldir automagically resets f_version to 0.
3184 */
3185 ns = filp->f_dentry->d_sb->s_fs_info;
3186 tid = (int)filp->f_version;
3187 filp->f_version = 0;
3188 for (task = first_tid(leader, tid, filp->f_pos - 2, ns);
3189 task;
3190 task = next_tid(task), filp->f_pos++) {
3191 tid = task_pid_nr_ns(task, ns);
3192 if (proc_task_fill_cache(filp, dirent, filldir, task, tid) < 0) {
3193 /* returning this tgid failed, save it as the first
3194 * pid for the next readir call */
3195 filp->f_version = (u64)tid;
3196 put_task_struct(task);
3197 break;
3198 }
3199 }
3200 out:
3201 put_task_struct(leader);
3202 out_no_task:
3203 return retval;
3204 }
3205
3206 static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
3207 {
3208 struct inode *inode = dentry->d_inode;
3209 struct task_struct *p = get_proc_task(inode);
3210 generic_fillattr(inode, stat);
3211
3212 if (p) {
3213 stat->nlink += get_nr_threads(p);
3214 put_task_struct(p);
3215 }
3216
3217 return 0;
3218 }
3219
3220 static const struct inode_operations proc_task_inode_operations = {
3221 .lookup = proc_task_lookup,
3222 .getattr = proc_task_getattr,
3223 .setattr = proc_setattr,
3224 };
3225
3226 static const struct file_operations proc_task_operations = {
3227 .read = generic_read_dir,
3228 .readdir = proc_task_readdir,
3229 };
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree